The use of LC-Orbitrap MS for the detection of Fusarium masked mycotoxins: the case of type A trichothecenes

'Masked mycotoxins' (mycotoxin glucosides) derived from type A trichothecenes (T-2 toxin and HT-2 toxin) were detected in commercially available maize powder reference material. These novel glucosides were identified as T-2 toxin-glucoside (T2-Glc) and HT-2 toxin-glucoside (HT2-Glc) on the basis of accurate mass measurements of characteristic ions and fragmentation patterns using high-resolution liquid chromatography Orbitrap mass spectrometric analysis. Although their absolute structures were not clarified, 3-OH glucosylation appeared to be the most probable when considering the structure of T-2 toxin and the fragment profiles of each masked mycotoxin. Concomitant detection of deoxynivalenol-3-glucoside (DON-3G) in the same material further supports this probability. According to an extrapolation based on the molar ratio DON-3G/DON (0.059), amounts of T2-Glc and HT2-Glc were estimated to be approximately 24 mu g/kg and 41 mu g/kg, respectively.